"Kraj" - land, state
If you say it is from Polish "kraj" how can it be jewish than?
Krajewski = Kraj +ew"ski" like other polish surname Majewski=Maj+ew"ski",
1. Common rule of creating polish surnames is that after word ending with "j" is mostly added endling like jewski, jski (less often anowski like Pij-anowski, -ewicz like Majewicz). Ending j+ewski i added more commonly than originally slavic j+ski because is easier to spell.
Ending -ski is 100% slavic you can find it commonly in Poland, Russia, Bulgaria and so on.
2. Word Kraj is 100% slavic. With etymology you said above. Krajać (cut material with scissors), Kroić (cut bread), Kraj/Kraina (country/state = country space cutted/ending by borders on map), sKraj (periferals, endind of lands - like in slavic country name uKRAIne ).
3. It can't be jewish because in Poland Jews were speaking Jiddish - smilar with German language and they mostly had surnames of german/jiddish origin. Also Jews couldnt use any -jewish ending and jewski is not slavisated version of -jewski because calling "jewish" is an english name(!). In Polish jewish i "Żyd-owski" and in Germany Jews were called "Jude".
4. Polonisation of jewish surnames happened at time of WWII when they tried to escape German Nazi Holocaust and german gettos or easier integrate in population under soviet occupation of Poland after WWII. They didnt add polish englind to jewish surnames they just take common polish surname to look more polish without any trace of "jewishness" and easier hide or pass the border.
5. Krajewski as Jewland? Nonsens. Maybe all Poles and Slavs are Jews than? Some comming from Chazaria had been converted into judaism and still have slavic blood but lets be serious. ;-)
Another slavic word for cutting but older is Rezać, Rzezać, Rząć, obrzezać(slavic name for jewish traditional cutting of... you know what ;) ), also slavic "rzeźnia" is slaughterhouse. Rezać/Rezat is so old slavic word that is even now used in Romania - former slavic country in ancient times but now nearly 100% romanisated.